Is this kid going to blow up his gun?

[44MAG#1]

OK people you do not crimp 9 mm at all there’s a lot of around you do not crimp. And it sounds like he’s running in the + P load range Not by my +P manual can check when I get home

I taper crimp fairly heavy on 9MM, 40 S&W, 10MM and 45 Auto.

[Texas Gun]

And 9mm 40/10mm 45acp
Head space off the mouth of the brass


I don't know why folks are advocating crimp to prevent set back. Set back happens because you don't have enough tension between the bullet and your case. In a straight walled cartridge like 9mm, this tension is achieved by pressing in a bullet that is slightly too big for the case. What holds your bullet is only this tension of the case neck against the sides of the bullet itself. The amount of force to press the bullet in further would continue to deform the case walls by stretching it. This takes a lot of force! Hence the press to get the bullet into the case in the first place.

A taper crimp overdone can undo this tension. The reason is that copper springs back more than lead does (even using jacketed bullets). You squeeze the bullet a bit inside the case, and the case later springs back a microscopic amount while the bullet itself does not to this extent. This reduces case tension. The taper crimp die should only be used to remove the bell created in order to easily place the bullet on the case mouth prior to seating it.

I use beveled lead 9mm bullets and do not bother crimping at all since I don't need to bell larger than the bullet diameter for easy seating.

[44MAG#1]

And 9mm 40/10mm 45acp
Head space off the mouth of the brass


I don't know why folks are advocating crimp to prevent set back. Set back happens because you don't have enough tension between the bullet and your case. In a straight walled cartridge like 9mm, this tension is achieved by pressing in a bullet that is slightly too big for the case. What holds your bullet is only this tension of the case neck against the sides of the bullet itself. The amount of force to press the bullet in further would continue to deform the case walls by stretching it. This takes a lot of force! Hence the press to get the bullet into the case in the first place.

A taper crimp overdone can undo this tension. The reason is that copper springs back more than lead does (even using jacketed bullets). You squeeze the bullet a bit inside the case, and the case later springs back a microscopic amount while the bullet itself does not to this extent. This reduces case tension. The taper crimp die should only be used to remove the bell created in order to easily place the bullet on the case mouth prior to seating it.

I use beveled lead 9mm bullets and do not bother crimping at all since I don't need to bell larger than the bullet diameter for easy seating.

I have been reloading for 51 years. Started out with just straightening out the flare then went to fairly heavy taper crimp and will not go back.
My case tension is fine without or with the fairly heavy taper crimp

[JimB..]

I have been reloading for 51 years. Started out with just straightening out the flare then went to fairly heavy taper crimp and will not go back.

Since I don’t apply a heavy crimp to autoloader rounds I’m curious, what is the big benefit? I’m good on accuracy, rounds neither set back nor pull. I’m willing to try, just want to know where I should look for improvement.

[44MAG#1]

Since I don’t apply a heavy crimp to autoloader rounds I’m curious, what is the big benefit? I’m good on accuracy, rounds neither set back nor pull. I’m willing to try, just want to know where I should look for improvement.

I never made any claims about anything. I have noticed the factories use a fairly heavy taper crimp on their premium ammo. The heavier taper crimp does seem like a more smooth transition into the barrel. I shoot Glocks and 1911's. I don't try to dream up reasons just to validate what I do. Accuracy with both crimps is good. I just use fairly heavy taper crimps on the cartridges I named and have had very good performance. So I continue to do it.

[megasupermagnum]

It seems like you haven't read Hornady 10th manual.

It was tongue in cheek humor.

[kenton]

I won't speak for 44mag#1 but I have seen my lower pressure sooty 38spl loads clean up once I started using a heavier roll crimp. I wonder if similar but lesser gains could be found with a heavy taper crimp. Additionally, I wonder if having the cartridge seat deeper into the chamber allows the boolit to start closer to engraving on the rifling helping with accuracy. Then we could open the can of worms that is the crimp jamming on the transition to the chamber lead further increasing chamber pressure and possibly improving combustion consistency. Or maybe that wouldn't happen...

[VariableRecall]

As a fairly new reloader and a Young'in myself, the stiffest load I've put into my 9mm handgun, a Hi-Point C9, is an experimental small-batch of 5gn of Win231 with a 124gn RN projectile. Being a blowback firearm and advertised as +P capable, it was able to handle it no problem. However, the slide "bottomed out" at every shot, which pretty quickly became uncomfortable after a magazine or two.
From my experience with it, my C9 appears most comfortable with a loading of around 4.4-4.8gn of powder. With anything below 4.2, the cases fail to provide a complete gas seal, but still cycle normally.

I still err on the side of starting from the lowest recommended, observe the brass to check if it's obturating properly, and work it up until I get a complete seal. Usually I try and see if can make my reloads nigh indistinguishable from factory by feel.

I'd say unless that kid has a +P capable handgun, he's asking for trouble.
One thing I'd suggest if you can contact him is he should try and directly compare factory ammo to his own loads, and work to make his stuff more like your average factory load.

[Idaho45guy]

As a fairly new reloader and a Young'in myself, the stiffest load I've put into my 9mm handgun, a Hi-Point C9, is an experimental small-batch of 5gn of Win231 with a 124gn RN projectile. Being a blowback firearm and advertised as +P capable, it was able to handle it no problem. However, the slide "bottomed out" at every shot, which pretty quickly became uncomfortable after a magazine or two.
From my experience with it, my C9 appears most comfortable with a loading of around 4.4-4.8gn of powder. With anything below 4.2, the cases fail to provide a complete gas seal, but still cycle normally.

I still err on the side of starting from the lowest recommended, observe the brass to check if it's obturating properly, and work it up until I get a complete seal. Usually I try and see if can make my reloads nigh indistinguishable from factory by feel.

I'd say unless that kid has a +P capable handgun, he's asking for trouble.
One thing I'd suggest if you can contact him is he should try and directly compare factory ammo to his own loads, and work to make his stuff more like your average factory load.

How did you end up down in AZ?? Last I saw you were going to WSU in Pullman and only had some older S&W. Hope you are doing well!

[VariableRecall]

How did you end up down in AZ?? Last I saw you were going to WSU in Pullman and only had some older S&W. Hope you are doing well!

I graduated and got a job over in Tempe! Not what I expected but hey, I'm employed now!

[Idaho45guy]

I graduated and got a job over in Tempe! Not what I expected but hey, I'm employed now!

Nice! I'll be in Yuma next weekend to pick up a motorcycle. Staying at a buddy's house up in New River for a night first. I like the area!